FFmpeg
eamad.c
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1 /*
2  * Electronic Arts Madcow Video Decoder
3  * Copyright (c) 2007-2009 Peter Ross
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Electronic Arts Madcow Video Decoder
25  * @author Peter Ross <pross@xvid.org>
26  *
27  * @see technical details at
28  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_MAD
29  */
30 
31 #include "avcodec.h"
32 #include "blockdsp.h"
33 #include "bytestream.h"
34 #include "bswapdsp.h"
35 #include "get_bits.h"
36 #include "aandcttab.h"
37 #include "eaidct.h"
38 #include "idctdsp.h"
39 #include "internal.h"
40 #include "mpeg12data.h"
41 #include "mpeg12vlc.h"
42 
43 #define EA_PREAMBLE_SIZE 8
44 #define MADk_TAG MKTAG('M', 'A', 'D', 'k') /* MAD I-frame */
45 #define MADm_TAG MKTAG('M', 'A', 'D', 'm') /* MAD P-frame */
46 #define MADe_TAG MKTAG('M', 'A', 'D', 'e') /* MAD lqp-frame */
47 
48 typedef struct MadContext {
56  unsigned int bitstream_buf_size;
57  DECLARE_ALIGNED(32, int16_t, block)[64];
59  uint16_t quant_matrix[64];
60  int mb_x;
61  int mb_y;
62 } MadContext;
63 
65 {
66  MadContext *s = avctx->priv_data;
67  s->avctx = avctx;
68  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
69  ff_blockdsp_init(&s->bdsp, avctx);
71  ff_idctdsp_init(&s->idsp, avctx);
75 
77  if (!s->last_frame)
78  return AVERROR(ENOMEM);
79 
80  return 0;
81 }
82 
83 static inline void comp(unsigned char *dst, ptrdiff_t dst_stride,
84  unsigned char *src, ptrdiff_t src_stride, int add)
85 {
86  int j, i;
87  for (j=0; j<8; j++)
88  for (i=0; i<8; i++)
89  dst[j*dst_stride + i] = av_clip_uint8(src[j*src_stride + i] + add);
90 }
91 
92 static inline void comp_block(MadContext *t, AVFrame *frame,
93  int mb_x, int mb_y,
94  int j, int mv_x, int mv_y, int add)
95 {
96  if (j < 4) {
97  unsigned offset = (mb_y*16 + ((j&2)<<2) + mv_y)*t->last_frame->linesize[0] + mb_x*16 + ((j&1)<<3) + mv_x;
98  if (offset >= (t->avctx->height - 7) * t->last_frame->linesize[0] - 7)
99  return;
100  comp(frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
101  frame->linesize[0],
102  t->last_frame->data[0] + offset,
103  t->last_frame->linesize[0], add);
104  } else if (!(t->avctx->flags & AV_CODEC_FLAG_GRAY)) {
105  int index = j - 3;
106  unsigned offset = (mb_y * 8 + (mv_y/2))*t->last_frame->linesize[index] + mb_x * 8 + (mv_x/2);
107  if (offset >= (t->avctx->height/2 - 7) * t->last_frame->linesize[index] - 7)
108  return;
109  comp(frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x * 8,
110  frame->linesize[index],
111  t->last_frame->data[index] + offset,
112  t->last_frame->linesize[index], add);
113  }
114 }
115 
116 static inline void idct_put(MadContext *t, AVFrame *frame, int16_t *block,
117  int mb_x, int mb_y, int j)
118 {
119  if (j < 4) {
121  frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
122  frame->linesize[0], block);
123  } else if (!(t->avctx->flags & AV_CODEC_FLAG_GRAY)) {
124  int index = j - 3;
126  frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x*8,
127  frame->linesize[index], block);
128  }
129 }
130 
131 static inline int decode_block_intra(MadContext *s, int16_t * block)
132 {
133  int level, i, j, run;
134  RLTable *rl = &ff_rl_mpeg1;
136  int16_t *quant_matrix = s->quant_matrix;
137 
138  block[0] = (128 + get_sbits(&s->gb, 8)) * quant_matrix[0];
139 
140  /* The RL decoder is derived from mpeg1_decode_block_intra;
141  Escaped level and run values a decoded differently */
142  i = 0;
143  {
144  OPEN_READER(re, &s->gb);
145  /* now quantify & encode AC coefficients */
146  for (;;) {
147  UPDATE_CACHE(re, &s->gb);
148  GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
149 
150  if (level == 127) {
151  break;
152  } else if (level != 0) {
153  i += run;
154  if (i > 63) {
156  "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
157  return -1;
158  }
159  j = scantable[i];
160  level = (level*quant_matrix[j]) >> 4;
161  level = (level-1)|1;
162  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
163  LAST_SKIP_BITS(re, &s->gb, 1);
164  } else {
165  /* escape */
166  UPDATE_CACHE(re, &s->gb);
167  level = SHOW_SBITS(re, &s->gb, 10); SKIP_BITS(re, &s->gb, 10);
168 
169  UPDATE_CACHE(re, &s->gb);
170  run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
171 
172  i += run;
173  if (i > 63) {
175  "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
176  return -1;
177  }
178  j = scantable[i];
179  if (level < 0) {
180  level = -level;
181  level = (level*quant_matrix[j]) >> 4;
182  level = (level-1)|1;
183  level = -level;
184  } else {
185  level = (level*quant_matrix[j]) >> 4;
186  level = (level-1)|1;
187  }
188  }
189 
190  block[j] = level;
191  }
192  CLOSE_READER(re, &s->gb);
193  }
194  return 0;
195 }
196 
198 {
199  int value = 0;
200  if (get_bits1(gb)) {
201  if (get_bits1(gb))
202  value = -17;
203  value += get_bits(gb, 4) + 1;
204  }
205  return value;
206 }
207 
208 static int decode_mb(MadContext *s, AVFrame *frame, int inter)
209 {
210  int mv_map = 0;
211  int av_uninit(mv_x), av_uninit(mv_y);
212  int j;
213 
214  if (inter) {
215  int v = decode210(&s->gb);
216  if (v < 2) {
217  mv_map = v ? get_bits(&s->gb, 6) : 63;
218  mv_x = decode_motion(&s->gb);
219  mv_y = decode_motion(&s->gb);
220  }
221  }
222 
223  for (j=0; j<6; j++) {
224  if (mv_map & (1<<j)) { // mv_x and mv_y are guarded by mv_map
225  int add = 2*decode_motion(&s->gb);
226  if (s->last_frame->data[0])
227  comp_block(s, frame, s->mb_x, s->mb_y, j, mv_x, mv_y, add);
228  } else {
229  s->bdsp.clear_block(s->block);
230  if(decode_block_intra(s, s->block) < 0)
231  return -1;
232  idct_put(s, frame, s->block, s->mb_x, s->mb_y, j);
233  }
234  }
235  return 0;
236 }
237 
238 static void calc_quant_matrix(MadContext *s, int qscale)
239 {
240  int i;
241 
243  for (i=1; i<64; i++)
244  s->quant_matrix[i] = (ff_inv_aanscales[i]*ff_mpeg1_default_intra_matrix[i]*qscale + 32) >> 10;
245 }
246 
248  void *data, int *got_frame,
249  AVPacket *avpkt)
250 {
251  const uint8_t *buf = avpkt->data;
252  int buf_size = avpkt->size;
253  MadContext *s = avctx->priv_data;
254  AVFrame *frame = data;
256  int width, height;
257  int chunk_type;
258  int inter, ret;
259 
260  bytestream2_init(&gb, buf, buf_size);
261 
262  chunk_type = bytestream2_get_le32(&gb);
263  inter = (chunk_type == MADm_TAG || chunk_type == MADe_TAG);
264  bytestream2_skip(&gb, 10);
265 
266  av_reduce(&avctx->framerate.den, &avctx->framerate.num,
267  bytestream2_get_le16(&gb), 1000, 1<<30);
268 
269  width = bytestream2_get_le16(&gb);
270  height = bytestream2_get_le16(&gb);
271  bytestream2_skip(&gb, 1);
272  calc_quant_matrix(s, bytestream2_get_byte(&gb));
273  bytestream2_skip(&gb, 2);
274 
275  if (bytestream2_get_bytes_left(&gb) < 2) {
276  av_log(avctx, AV_LOG_ERROR, "Input data too small\n");
277  return AVERROR_INVALIDDATA;
278  }
279 
280  if (width < 16 || height < 16) {
281  av_log(avctx, AV_LOG_ERROR, "Dimensions too small\n");
282  return AVERROR_INVALIDDATA;
283  }
284 
285  if (avctx->width != width || avctx->height != height) {
287  if((width * (int64_t)height)/2048*7 > bytestream2_get_bytes_left(&gb))
288  return AVERROR_INVALIDDATA;
289  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
290  return ret;
291  }
292 
293  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
294  return ret;
295 
296  if (inter && !s->last_frame->data[0]) {
297  av_log(avctx, AV_LOG_WARNING, "Missing reference frame.\n");
299  if (ret < 0)
300  return ret;
301  memset(s->last_frame->data[0], 0, s->last_frame->height *
302  s->last_frame->linesize[0]);
303  memset(s->last_frame->data[1], 0x80, s->last_frame->height / 2 *
304  s->last_frame->linesize[1]);
305  memset(s->last_frame->data[2], 0x80, s->last_frame->height / 2 *
306  s->last_frame->linesize[2]);
307  }
308 
311  if (!s->bitstream_buf)
312  return AVERROR(ENOMEM);
313  s->bbdsp.bswap16_buf(s->bitstream_buf, (const uint16_t *)(buf + bytestream2_tell(&gb)),
314  bytestream2_get_bytes_left(&gb) / 2);
317 
318  for (s->mb_y=0; s->mb_y < (avctx->height+15)/16; s->mb_y++)
319  for (s->mb_x=0; s->mb_x < (avctx->width +15)/16; s->mb_x++)
320  if(decode_mb(s, frame, inter) < 0)
321  return AVERROR_INVALIDDATA;
322 
323  *got_frame = 1;
324 
325  if (chunk_type != MADe_TAG) {
327  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
328  return ret;
329  }
330 
331  return buf_size;
332 }
333 
335 {
336  MadContext *t = avctx->priv_data;
338  av_freep(&t->bitstream_buf);
339  return 0;
340 }
341 
343  .name = "eamad",
344  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts Madcow Video"),
345  .type = AVMEDIA_TYPE_VIDEO,
346  .id = AV_CODEC_ID_MAD,
347  .priv_data_size = sizeof(MadContext),
348  .init = decode_init,
349  .close = decode_end,
350  .decode = decode_frame,
351  .capabilities = AV_CODEC_CAP_DR1,
352 };
AVRational framerate
Definition: avcodec.h:3111
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
void(* bswap16_buf)(uint16_t *dst, const uint16_t *src, int len)
Definition: bswapdsp.h:26
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
AVCodec ff_eamad_decoder
Definition: eamad.c:342
float re
Definition: fft.c:82
uint16_t quant_matrix[64]
Definition: eamad.c:59
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
av_cold void ff_mpeg12_init_vlcs(void)
Definition: mpeg12.c:137
static void comp_block(MadContext *t, AVFrame *frame, int mb_x, int mb_y, int j, int mv_x, int mv_y, int add)
Definition: eamad.c:92
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
void(* clear_block)(int16_t *block)
Definition: blockdsp.h:36
BlockDSPContext bdsp
Definition: eamad.c:50
Scantable.
Definition: idctdsp.h:31
MPEG-1/2 VLC.
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1484
av_cold void ff_blockdsp_init(BlockDSPContext *c, AVCodecContext *avctx)
Definition: blockdsp.c:60
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1781
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:70
uint8_t permutated[64]
Definition: idctdsp.h:33
uint8_t run
Definition: svq3.c:206
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3495
RLTable.
Definition: rl.h:39
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:359
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:443
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:112
#define height
uint8_t * data
Definition: avcodec.h:1483
bitstream reader API header.
void ff_ea_idct_put_c(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
Definition: eaidct.c:80
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
#define AV_CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:889
static void calc_quant_matrix(MadContext *s, int qscale)
Definition: eamad.c:238
#define av_log(a,...)
AVCodecContext * avctx
Definition: eamad.c:49
IDCTDSPContext idsp
Definition: eamad.c:52
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:178
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1651
const char * name
Name of the codec implementation.
Definition: avcodec.h:3502
static av_cold int decode_end(AVCodecContext *avctx)
Definition: eamad.c:334
static int decode_block_intra(MadContext *s, int16_t *block)
Definition: eamad.c:131
#define CLOSE_READER(name, gb)
Definition: get_bits.h:149
#define GET_RL_VLC(level, run, name, gb, table, bits,max_depth, need_update)
Definition: get_bits.h:738
#define SKIP_BITS(name, gb, num)
Definition: get_bits.h:193
av_cold void ff_init_scantable_permutation(uint8_t *idct_permutation, enum idct_permutation_type perm_type)
Definition: idctdsp.c:50
#define width
ScanTable scantable
Definition: eamad.c:58
int width
picture width / height.
Definition: avcodec.h:1744
RLTable ff_rl_mpeg1
Definition: mpeg12data.c:166
int16_t block[64]
Definition: eamad.c:57
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eamad.c:247
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:199
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:96
RL_VLC_ELEM * rl_vlc[32]
decoding only
Definition: rl.h:48
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:211
static int decode210(GetBitContext *gb)
Definition: get_bits.h:841
static void comp(unsigned char *dst, ptrdiff_t dst_stride, unsigned char *src, ptrdiff_t src_stride, int add)
Definition: eamad.c:83
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:188
GetBitContext gb
Definition: eamad.c:54
#define MADe_TAG
Definition: eamad.c:46
Libavcodec external API header.
static void idct_put(MadContext *t, AVFrame *frame, int16_t *block, int mb_x, int mb_y, int j)
Definition: eamad.c:116
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
const uint16_t ff_inv_aanscales[64]
Definition: aandcttab.c:38
main external API structure.
Definition: avcodec.h:1571
MPEG-1/2 tables.
#define OPEN_READER(name, gb)
Definition: get_bits.h:138
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1968
static int decode_motion(GetBitContext *gb)
Definition: eamad.c:197
void * buf
Definition: avisynth_c.h:766
int mb_y
Definition: eamad.c:61
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
int index
Definition: gxfenc.c:89
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
const uint16_t ff_mpeg1_default_intra_matrix[256]
Definition: mpeg12data.c:30
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:98
BswapDSPContext bbdsp
Definition: eamad.c:51
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
#define MADm_TAG
Definition: eamad.c:45
AAN (Arai, Agui and Nakajima) (I)DCT tables.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
uint8_t level
Definition: svq3.c:207
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:212
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
common internal api header.
#define TEX_VLC_BITS
Definition: dv.h:99
void * bitstream_buf
Definition: eamad.c:55
int den
Denominator.
Definition: rational.h:60
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:796
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
void * priv_data
Definition: avcodec.h:1598
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
av_cold void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
Definition: idctdsp.c:238
static int decode_mb(MadContext *s, AVFrame *frame, int inter)
Definition: eamad.c:208
int mb_x
Definition: eamad.c:60
#define av_uninit(x)
Definition: attributes.h:148
int height
Definition: frame.h:353
#define av_freep(p)
AVFrame * last_frame
Definition: eamad.c:53
unsigned int bitstream_buf_size
Definition: eamad.c:56
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1460
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1182
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:987
static av_cold int decode_init(AVCodecContext *avctx)
Definition: eamad.c:64